Abstract: This paper comprehensively analyzes the changes of meteorological elements and reference crop evapotranspiration （ET₀） under the influence of aerosol in Luoyang during an air pollution process in western Henan from 20∶00 on June 15 to 8∶00 on June 20,2016.WRF-Chem bidirectional feedback test is used to quantify the changes,and the accuracy of simulation results is verified by meteorological observation data,so as to further analyze the influence of aerosol on ET₀ and its mechanism.The research findings show that in this process of air pollution,the PM_2.5 concentration in Luoyang is generally high,and that the peaks mostly occur in the morning and evening.The PM_2.5 concentration in the northeast of Luoyang is generally higher than that in the southwest.The presence of aerosol changes various meteorologi‐cal elements in Luoyang,which leads to the change of ET₀,and theΔET₀ of each site is between -0.23～0.33 mm/d.Affected by aerosol,the variation range of ET_0-d is-0.26～0.04 mm/d,which is more than that of ET_0-n （-0.08～0.02 mm/d）.The variation of the aerodynamic term(ET_0-A) at each site is more than the radiation term (ET_0-R),which also dominates the variation of ET₀ in various parts of Luoyang.